Metal injection molded heat dissipation device

ABSTRACT

A heat dissipation device is provided. The heat dissipation device includes an integrated heat spreader and a base plate coupled to the integrated heat spreader, wherein the base plate comprises a plurality of metal pellets to dissipate heat from the integrated heat spreader.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is related and claims priority to U.S. patentapplication Ser. No. 12/323,318 titled “METAL INJECTION MOLDED HEATDISSIPATION DEVICE” which was filed on Nov. 25, 2008; this applicationis entirely incorporated by reference.

BACKGROUND

With recent advancements in the semiconductor manufacturing technologymicroelectronic components are becoming smaller and circuitry withinsuch components is becoming increasingly dense. As the circuit densityincreases, heat generation from such components also increases. Varioustechniques are employed to dissipate the heat generated from thecomponents. For example, a heat dissipating device such as an integratedheat spreader and a heat sink such as a multi-fin heat sink may beemployed to dissipate the generated heat to the surrounding environment.

The multi-fin heat sink includes thin densely packed fin arrays thatrely on very small hydraulic diameters in fluid channels between fins togenerate heat transfer coefficients for dissipating the heat to thesurrounding environment. However, manufacturing of these fin arrays is achallenge and is quite expensive. Further, additional components such asa pump may be required to provide the adequate pressure for use of suchheat sinks.

BRIEF DESCRIPTION OF THE DRAWINGS

Features of embodiments of the claimed subject matter will becomeapparent as the following detailed description proceeds, and uponreference to the drawings, in which like numerals depict like parts, andin which:

FIG. 1 illustrates a microelectronic package in accordance withembodiments of present technique;

FIG. 2 illustrates an exemplary method for forming a microelectronicpackage in accordance with embodiments of present technique;

FIG. 3 illustrates an exemplary configuration of a metal injectionmolded base plate coupled to an integrated heat spreader in accordancewith embodiments of present technique;

FIG. 4 illustrates an exemplary zoomed view of a portion of the metalinjection molded base plate of FIG. 3 in accordance with embodiments ofpresent technique;

FIG. 5 illustrates an exemplary configuration of the metal injectionmolded base plate coupled to the integrated heat spreader in accordancewith embodiments of present technique; and

FIG. 6 illustrates an embodiment of a computer system.

Although the following Detailed Description will proceed with referencebeing made to illustrative embodiments of the claimed subject matter,many alternatives, modifications, and variations thereof will beapparent to those skilled in the art. Accordingly, it is intended thatthe claimed subject matter be viewed broadly, and be defined only as setforth in the accompanying claims.

DETAILED DESCRIPTION

As discussed in detail below, the embodiments of the present inventionfunction to provide a heat dissipation device for dissipating the heatfrom a microelectronic package. In particular, the technique uses ametal injection molded base plate having a plurality of metal pelletsthat function as microfins to dissipate the heat from themicroelectronic package.

References in the specification to “one embodiment”, “an embodiment”,“an exemplary embodiment”, indicate that the embodiment described mayinclude a particular feature, structure, or characteristic, but everyembodiment may not necessarily include the particular feature,structure, or characteristic. Moreover, such phrases are not necessarilyreferring to the same embodiment. Further, when a particular feature,structure, or characteristic is described in connection with anembodiment, it is submitted that it is within the knowledge of oneskilled in the art to affect such feature, structure, or characteristicin connection with other embodiments whether or not explicitlydescribed.

The following description includes terms, such as top, bottom etc. thatare used for descriptive purposes only and are not to be construed aslimiting. The embodiments of the device or article described herein canbe manufactured or used in a number of positions and orientations.

Referring first to FIG. 1, a microelectronic package 10 is illustrated.The microelectronic package 10 includes a substrate 12 and a die 14coupled to the substrate 12. The substrate 12 may be formed of a varietyof materials including ceramic and printed circuit boards. Further, thesubstrate 12 may be a one-layer board or a multi-layer board. In certainembodiments, the die 14 forms one of a data storage device, a digitalsignal processor, a micro-controller and a hand-held device. Typically,the die 14 is attached to one side of the substrate 12 and theattachment may be through a plurality of solder balls or solder bumpconnections (not shown), among other attachment methods.

The microelectronic package 10 includes an integrated heat spreader(IHS) 16 and a base plate 18 coupled to the integrated heat spreader 16for dissipating the heat generated from the microelectronic package 10to the surrounding environment. The integrated heat spreader 16 may beformed of a suitable conductive material such as copper, aluminum andcarbon composites, among others. In certain embodiments, the base plate18 may be directly coupled to the die 14. Further, in certainembodiments, the base plate 18 is in thermal contact with the integratedheat spreader 16 through a thermal interface material (not shown).Examples of the thermal interface material include, but are not limitedto, a grease, a polymer, a solder and a polymer solder hybrid (PSH). Inthis exemplary embodiment, the base plate 18 includes a plurality ofsolid conducting pellets (not shown) to facilitate the heat dissipationto the surrounding environment. In certain embodiments, the base plate18 includes a plurality of metal pellets. In one exemplary embodiment,the base plate 18 comprises a metal injection molded plate having aplurality of copper pellets. In another exemplary embodiment, the baseplate 18 comprises a metal injection molded plate having a plurality ofaluminum pellets. However, other metals such as magnesium, tungsten,nickel and silver may be employed as the metal pellets for the baseplate 18. In certain other embodiments, alloys of metals such asmagnesium, tungsten, nickel, silver, brass and bronze may be employedfor the conducting pellets for the base plate 18.

The plurality of metal pellets function as microfins to dissipate theheat from the microelectronic package 10 to the surrounding environment.In certain embodiments, a coolant fluid such as water may be circulatedthrough the plurality of metal pellets to facilitate the heatdissipation. In one exemplary embodiment, a porosity of the base plate18 with the plurality of metal pellets is between about 10% to about50%. In one exemplary embodiment, a size of each of the plurality ofmetal pellets is between about 25 microns and about 400 microns. In oneexemplary embodiment, the size of each of the plurality of metal pelletsis about 200 microns. It should be noted that metal pellets havingvarying sizes may be employed for the base plate 18.

In the microelectronic package 10, the integrated heat transfer device16 is in thermal contact with the die 14 through a thermal interfacematerial (TIM) 20. As illustrated, the thermal interface material 20 isdisposed between the die 14 and the integrated heat spreader 16.Examples of the thermal interface material 20 include, but are notlimited to, a grease, a polymer, a solder and a polymer solder hybrid(PSH).

In operation, heat is typically conducted from the die 14 through thethermal interface material 20 to the integrated heat spreader 16 by heatconduction. Further, the heat is transferred from the integrated heatspreader 16 to the base plate 18 and the convective heat transferprimarily transfers the heat from the base plate 18 to the surroundingenvironment. In certain embodiments, a base plate 18 is coupled to theintegrated heat spreader 16 through a thermal interface material (notshown) to facilitate the heat transfer from the integrated heat spreader16 to the base plate 18.

FIG. 2 illustrates an exemplary method 30 for forming a microelectronicpackage. At block 32, an integrated heat spreader is provided. Further,a metal injection molded base plate is coupled to a top surface of theintegrated heat spreader (block 34). In this embodiment, the metalinjection molded base plate includes a plurality of metal pellets thatfunction as microfins to dissipate heat from the integrated heatspreader. In one exemplary embodiment, the metal injection molded baseplate includes a plurality of copper pellets. In another exemplaryembodiment, the metal injection molded base plate includes a pluralityof aluminum pellets. However, other metals may be used for the metalpellets. In certain embodiments, a porosity of the base plate with themetal pellets is between about 10% and about 50%. In one exemplaryembodiment, the porosity of the base plate with the metal pellets isbetween 10% and about 20%.

At block 36, a die is coupled to a bottom surface of the integrated heatspreader. In certain embodiments, the die forms one of a data storagedevice, a digital signal processor, a micro-controller and a hand-helddevice. In certain embodiments, the integrated heat spreader is inthermal contact with the die through a thermal interface material (TIM).Examples of the thermal interface material include, but are not limitedto, a grease, a polymer, a solder and a polymer solder hybrid (PSH). Incertain embodiments, the integrated heat spreader is coupled to the dieto form a package. Subsequently the base plate is coupled to thepackage. In certain embodiments, a thermal interface material isemployed between the base plate and the integrated heat spreader.

In this exemplary embodiment, an inlet hose and an outlet hose iscoupled to the metal injection molded base plate for circulating acoolant fluid within the plurality of metal pellets. In one exemplaryembodiment, the coolant fluid includes water. Further a sealant materialmay be disposed adjacent to the metal injection molded base plate toprevent any leakage of the coolant fluid. FIGS. 3 and 5 illustrateexemplary configurations of the metal injection molded base platecoupled to the integrated heat spreader.

FIG. 3 illustrates an exemplary configuration 50 of a metal injectionmolded base plate 52 coupled to an integrated heat spreader 54. In theillustrated embodiments, the metal injection molded base plate 52includes a plurality of metal pellets (not shown) that function asmicrofins to dissipate the heat from the integrated heat spreader. Inthis exemplary embodiment, the metal injection molded base plate 52 iscoupled to the integrated heat spreader 54 through a thermal interfacematerial 56. Examples of the thermal interface material 56 include, butare not limited to, a grease, a polymer, a solder and a polymer solderhybrid (PSH). As previously described, the metal injection molded baseplate 52 may be coupled to a silicon bare die or any other electroniccomponent package.

An inlet hose coupling 58 with an coupled inlet hose (not shown) and anoutlet hose coupling 60 with an coupled outlet hose (not shown) isconnected to the metal injection molded base plate 52 for circulating acoolant fluid (not shown) such as water through the plurality of metalpellets. The coolant fluid facilitates the heat dissipation to thesurrounding environment. In operation, the coolant fluid is introducedinto the metal injection molded base plate 52 through the inlet hosecoupling 58, as represented by reference numeral 62. Further, thecoolant fluid absorbs the heat as it passes through the metal injectionmolded base plate 52, as represented by reference numeral 64. Thecoolant fluid is subsequently removed through the outlet hose coupling60, as represented by reference numeral 66.

In the illustrated embodiment, the inlet and outlet hose couplings 58and 60 are coupled to the metal injection molded base plate 52 throughthreaded hose connectors 68 and 70 respectively. However, a variety ofcoupling mechanisms may be employed to couple the inlet and outlet hosecouplings 58 and 60 to the metal injection molded base plate 52.Further, a sealant material 72 is disposed adjacent to the metalinjection molded base plate 52 to prevent leakage of the coolant fluid.In one exemplary embodiment, the sealant material 72 includes eutecticsolder. Other examples of the sealant material 72 include, but are notlimited to, electroless nickel plating, chrome and zinc plating.

FIG. 4 illustrates an exemplary zoomed view 80 of a portion of the metalinjection molded base plate 52 of FIG. 3. As illustrated, the metalinjection molded base plate 80 includes a plurality of metal pelletssuch as represented by reference numeral 82. In one exemplaryembodiment, the metal injection molded base plate includes a pluralityof copper pellets 82. In another exemplary embodiment, the metalinjection molded base plate includes a plurality of aluminum pellets 82.However, a variety of other metals may be employed for the metal pellets82. In this exemplary embodiment, the plurality of metal pellets 82 arecoupled for providing a thermally conductive path between the solidmaterial and an open porous path for the fluid.

In certain embodiments, the heat dissipation through the metal injectionmolded base plate 82 is based upon a porosity of metal injection moldedbase plate with the metal pellets 82. In one embodiment, the porosity ofthe metal injection molded base plate 82 is between about 10% and about50%. In one exemplary embodiment, the porosity of the metal injectionmolded base plate 82 is between about 10% and about 20%. In oneexemplary embodiment and a combination of sizes of each of the pluralityof metal pellets 82 is between 25 microns and about 400 microns. In oneexemplary embodiment, the size of each of the plurality of metal pelletsis about 200 microns. It should be noted that metal pellets 82 havingvarying sizes may be employed for the base plate 18.

FIG. 5 illustrates another exemplary configuration 90 of the metalinjection molded base plate 52 (see FIG. 3) coupled to the integratedheat spreader 54 (see FIG. 3). As with the configuration 50 of FIG. 3,the metal injection molded base plate 52 is coupled to the integratedheat spreader through the thermal interface material 56. In thisexemplary embodiment, the inlet and outlet hose couplings 58 and 60 arecoupled to the metal injection molded base plate 52 through solderedconnectors 92 and 94 respectively. Again, a coolant fluid such as wateris circulated through the metal injection molded base plate 52 throughthe inlet and outlet hose couplings 58 and 60, as represented byreference numerals 62, 64 and 66. The coolant fluid passes through theplurality of metal pellets 82 (see FIG. 4) of the metal injection moldedbase plate 52 which facilitate the heat transfer to the surroundingenvironment.

The microelectronic package described above may be disposed in acomputer system, a wireless communicator and a hand-held device. FIG. 6illustrates an embodiment of a computer system 100. The computer system100 includes a bus 102 to which the various components are coupled. Incertain embodiments, the bus 102 includes a collection of a plurality ofbuses such as a system bus, a Peripheral Component Interface (PCI) bus,a Small Computer System Interface (SCSI) bus, etc. Representation ofthese buses as a single bus 102 is provided for ease of illustration,and it should be understood that the system 100 is not so limited. Thoseof ordinary skill in the art will appreciate that the computer system100 may have any suitable bus architecture and may include any number ofcombination of buses.

A processor 104 is coupled to the bus 102. The processor 104 may includeany suitable processing device or system, including a microprocessor(e.g., a single core or a multi-core processor), a network processor, anapplication specific integrated circuit (ASIC), or a field programmablegate array (FPGA), or any similar device. It should be noted thatalthough FIG. 6 shows a single processor 104, the computer system 100may include two or more processors.

The computer system 100 further includes system memory 106 coupled tothe bus 102. The system memory 106 may include any suitable type andnumber of memories, such as static random access memory (SRAM), dynamicrandom access memory (DRAM), synchronous dynamic random access memory(SDRAM), or double data rate DRAM (DDRDRAM). During operation of thecomputer system 100, an operating system and other applications may beresident in the system memory 106.

The computer system 100 may further include a read-only memory (ROM) 108coupled to the bus 102. The ROM 108 may store instructions for theprocessor 104. The computer system 100 may also include a storage device(or devices) 110 coupled to the bus 102. The storage device 110 includesany suitable non-volatile memory, such as, for example, a hard diskdrive. The operating system and other programs may be stored in thestorage device 110. Further, a device 112 for accessing removablestorage media (e.g., a floppy disk drive or a CD ROM drive) may becoupled to the bus 102.

The computer system 100 may also include one or more Input/Output (I/O)devices 114 coupled to the bus 102. Common input devices includekeyboards, pointing devices such as a mouse, as well as other data entrydevices. Further, common output devices include video displays, printingdevices, and audio output devices. It will be appreciated that these arebut a few examples of the types of I/O devices that may be coupled tothe computer system 100.

The computer system 100 may further comprise a network interface 116coupled to the bus 102. The network interface 116 comprises any suitablehardware, software, or combination of hardware and software that iscapable of coupling the system 100 with a network (e.g., a networkinterface card). The network interface 116 may establish a link with thenetwork over any suitable medium (e.g., wireless, copper wire, fiberoptic, or a combination thereof) supporting exchange of information viaany suitable protocol such as TCP/IP (Transmission Controlprotocol/Internet Protocol), HTTP (Hyper-Text Transmission Protocol, aswell as others.

It should be understood that the computer system 100 illustrated in FIG.6 is intended to represent an embodiment of such a system and, further,that this system may include any additional components, which have beenomitted for clarity and ease of understanding. By way of example, thesystem 100 may include a direct memory access (DMA) controller, a chipset associated with the processor 104, additional memory (e.g., cachememory) as well as additional signal lines and buses. Also, it should beunderstood that the computer system 100 may not include all thecomponents shown in FIG. 6. The computer system 100 may comprise anytype of computing device, such as a desktop computer, a laptop computer,a server, a hand-held computing device, a wireless communication device,an entertainment system etc.

In this embodiment, the computer system 100 may include the device asdescribed in the embodiments above. By way of example, the processor 104may include a heat dissipation device that includes an integrated heatspreader and a base plate coupled to the integrated heat spreader,wherein the base plate comprises a plurality of metal pellets todissipate heat from the integrated heat spreader.

The foregoing detailed description and accompanying drawings are onlyillustrative and not restrictive. They have been provided primarily fora clear and comprehensive understanding of the disclosed embodiments andno unnecessary limitations are to be understood therefrom. Numerousadditions, deletions, and modifications to the embodiments describedherein, as well as alternative arrangements, may be devised by thoseskilled in the art without departing from the spirit of the disclosedembodiments and the scope of the appended claims.

The invention claimed is:
 1. A base plate for dissipating heat whereinthe base plate is a metal injection molded plate, and the base platecomprises a plurality of conducting pellets.
 2. The base plate of claim1, wherein the base plate is coupled with an integrated heat spreader.3. The base plate of claim 1, wherein the plurality of conductingpellets comprises a plurality of copper pellets.
 4. The base plate ofclaim 1, wherein the plurality of conducting pellets comprises aplurality of aluminum pellets.
 5. The base plate of claim 1, wherein aporosity of the plurality of conducting pellets is between about 10% andabout 50%.
 6. The base plate of claim 1, wherein a size of each of theplurality of conducting pellets is between about 20 microns and 400microns.
 7. The base plate of claim 1, further comprising inlet andoutlet hose couplings coupled to the base plate, wherein the inlet andoutlet hose couplings are to circulate a coolant fluid through theplurality of conducting pellets of the base plate.
 8. The base plate ofclaim 7, wherein the inlet and outlet hose couplings are coupled to thebase plate through threaded hose connectors.
 9. The base plate of claim7, wherein the inlet and outlet hose couplings are coupled to the baseplate through soldered hose connectors.
 10. The base plate of claim 7,further comprising a sealant material disposed adjacent to the baseplate to substantially prevent leakage of the coolant fluid from thebase plate.
 11. The base plate of claim 10, wherein the sealant materialcomprises eutectic solder.
 12. A microelectronic package, comprising abase plate that is a metal injection molded plate, wherein the baseplate comprises a plurality of conducting pellets to dissipate heat froman integrated heat spreader.
 13. The microelectronic package of claim12, wherein the plurality of conducting pellets comprises a plurality ofcopper pellets.
 14. The microelectronic package of claim 12, wherein theplurality of conducting pellets comprises a plurality of aluminumpellets.
 15. The microelectronic package of claim 12, wherein a porosityof the base plate with the plurality of metal pellets is between about10% and about 50%.
 16. A method of forming a base plate, comprising: ametal injection molded plate, wherein the metal injection molded plateemploys a plurality of conducting pellets to dissipate heat.
 17. Themethod of claim 16, further comprising coupling inlet and outlet hosecouplings to the metal injection molded base plate for circulating acoolant fluid within the plurality of metal pellets.
 18. The method ofclaim 16, wherein the plurality of conducting pellets comprises aplurality of copper pellets.
 19. The method of claim 16, wherein theplurality of conducting pellets comprises a plurality of aluminumpellets.
 20. The method of claim 16, further comprising disposing asealant material adjacent to the metal injection molded plate.
 21. Thebase plate of claim 1, wherein a porosity of the plurality of conductingpellets is between 10% and 50%.
 22. The base plate of claim 1, wherein asize of each of the plurality of conducting pellets is between 20microns and 400 microns.
 23. The base plate of claim 1, wherein aporosity of the plurality of conducting pellets is between substantially10% and substantially 50%.
 24. The base plate of claim 1, wherein a sizeof each of the plurality of conducting pellets is between substantially20 microns and substantially 400 microns.